1. Technical Field
The present disclosure relates generally to media error detection, and in particular, to detection of media errors in disks proximate to previously found media errors.
2. Related Art
Latent sector errors (LSEs) that occur on hard disk drives (HDDs) within a redundant array of independent disk (RAID) subsystem are typically recoverable when the RAID group is otherwise healthy. However, if RAID redundancy is already compromised (due to disk failure, as an example), the detection of an LSE on the redundant drive typically means data-loss has occurred.
Traditional RAID subsystems attempt to mitigate the probability of hitting this condition via background data scrub operations designed to find and repair LSEs prior to occurrence of data loss following a disk failure. However, if an LSE is found in response to a host input/output (I/O), most RAID subsystems repair the single specific LSE encountered (using RAID) and complete the associated I/O to the host, but do nothing to expedite the discovery and repair of LSEs that likely lie in wait within the logically adjacent address ranges. If a disk failure occurs prior to the background data scrub operation gets to the affected area of disk, data loss will have occurred.